Evaluation of ultrafiltration for determining molecular weight of fulvic acid

G. R. Aiken

doi:10.1021/es00130a016

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Evaluation of ultrafiltration for determining molecular weight of fulvic acid

G. R. Aiken

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Abstract

Two commonly used ultrafiltration membranes are evaluated for the determination of molecular weights of humic substances. Polyacrylic acids of Mr 2000 and 5000 and two well-characterized fulvic acids are used as standards. Molecular size characteristics of standards, as determined by small-angle X-ray scattering, are presented. Great care in evaluating molecular weight data obtained by ultrafiltration is needed because of broad nominal cutoffs and membrane-solute interactions.

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G. R. Aiken. 2002-05-01. Evaluation of ultrafiltration for determining molecular weight of fulvic acid. https://doi.org/10.1021/es00130a016

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